The Drug Enforcement Administration allowed drugmakers to substantially increase the number of opioids they produced each year even as the number of opioid-related overdoses in the U.S. grew, according to a review released Oct. 1 by the Office of the Inspector General.

The DEA, part of the Justice Department, is responsible for regulating access to opioids, including production of the drugs and diversion concerns.

The inspector general found that the DEA was "slow to respond" to the opioid crisis and noted that more than 300,000 people have died of opioid overdoses since 2000.

The rate of opioid overdose deaths in the U.S. grew on average by 8 percent per year from 1999 to 2013 and by 71 percent per year from 2013 to 2017, the report found. Despite overdose deaths growing, the DEA was authorizing drugmakers to produce substantially larger amounts of opioids from 2003 to 2013.

In fact, the DEA increased oxycodone production quotas by about 400 percent from 2002 to 2013 despite evidence that opioids were being overprescribed and misused, according to the report.

"We found that the [Justice] Department and DEA have recently taken steps to address the opioid epidemic, but more work remains," the report stated.

The DEA said in a statement to The New York Times that it removed roughly 900 licenses to handle controlled substances every year for the last eight years.